Molecular design, characterization, and application of multi-information dyes for multi-dimensional optical chemical sensing. Molecular design concepts of the dyes and their fundamental spectral characteristics Original Research Article

The molecular design of multi-functional dyes, called `multi-information dyesʹ (MIDs), and their application to several methods of optical chemical sensing were proposed. The concepts for the molecular design of the dyes were as follows: (1) the introduction of multiple (both positive and negative) charges on both ends of the large conjugated π-electron system of the dye molecule, so that the dye interacts with many chemical species or environments; (2) the introduction of different substitution (electron-donating or electron-accepting) groups in the conjugated π-electron system of the dye molecule, so that the dye has a different pKa and solvatochromic property; and (3) the introduction of an immobilization site in the dye molecule, so that the dye can be easily prepared as a sensing probe.